Direct-sequence spread-spectrum using directionally constrained adaptive beam forming to null interference

Applications Of Antenna Arrays To Mobile Communications, Part I: Performance Improvement, Feasibility, And System Considerations

“…The use of constrained beam forming for mobile communications is discussed in [19] and [71]- [73]. For proper operation, the direction of the desired signal is required.…”

“…An application of adaptive arrays to cancel interferences in a satellite-to-satellite communications system using direct-sequence spread spectrum is considered in [73]. A constrained beam-forming algorithm, which uses the direction of the desired signal as well as an adaptive beam forming using the reference signal, is studied for this application.…”

“…In situations where the precise direction of the signal is known, interference cancellation may be achieved by solving a constrained beam-forming problem, whereas when this is not the case, it may be achieved by using a reference signal as discussed in [73] and [138], where the reference signal for a CDMA system is generated by code synchronization. A comparison of the two schemes [73] for a satellite-to-satellite communications scenario when an approximate direction of the signal is known indicates that the constrained scheme cancels the interference faster than the reference generation scheme.…”

“…A comparison of the two schemes [73] for a satellite-to-satellite communications scenario when an approximate direction of the signal is known indicates that the constrained scheme cancels the interference faster than the reference generation scheme.…”

Augmentation of Anti-Jam GPS System Using Smart Antenna With a Simple Doa Estimation Algorithm

“…An adaptive array is an antenna system that can modify its beam pattern or other parameters, by means of internal feedback control while the antenna system is operating. Adaptive arrays are also known as adaptive beam formers or adaptive antennas [1][2][3][4]. A simple narrowband adaptive array is shown in Figure 1.…”